Biologists have long maintained that two groups of pinnipeds, sea lions and walruses, are descended from a terrestrial bear like animal, whereas the remaining group, seals, shares an ancestor with weasels. But the recent discovery of detailed similarities in the skeletal structure of the flippers in all three groups undermines the attempt to explain away superficial resemblance as due to convergent evolution-the independent development of similarities between unrelated groups in response to similar environmental pressures. Flippers may indeed be a necessary response to aquatic life, turtles, whales, and dugongs also have them. But the common detailed design found among the pinnipeds probably indicates a common ancestor. Moreover, walruses and seals drive themselves through the water with thrusts of their hind flippers, but sea lions use their front flippers. If anatomical similarity in the flippers resulted from similar environmental pressures, as posited by the convergent-evolution theory, one would expect walruses and seals, but not seals and sea lions, to have similar flippers.
1.The author implies that which of the following was part of the long-standing view concerning pinnipeds?
(A) Pinnipeds are all descended from a terrestrial bear like animal.
(B) Pinnipeds share a common ancestor with turtles, whales, and dugongs.
(C) Similarities among pinnipeds are due to their all having had to adapt to aquatic life.
(D) There are detailed similarities in the skeletal structure of the flippers in all pinnipeds.
(E) Convergent evolution cannot account for the similarities among pinnipeds.
2.The author implies which of the following about the fact that turtles, whales, and dugongs all have flippers?
(A) It can be explained by the hypothesis that turtles, whales, and dugongs are very closely related.
(B) It can be explained by the idea of convergent evolution.
(C) It suggests that turtles, whales, and dugongs evolved in separate parts of the world.
(D) It undermines the view that turtles, whales, and dugongs are all descended from terrestrial ancestors.
(E) It is the primary difference between turtles, whales, and dugongs, on the one hand, and pinnipeds, on the other.
3.In presenting the argument in the passage, the author does which of the following?
(A) Contends that key terms in an opposing view have been improperly used.
(B) Contends that opponents have purposely obscured important evidence.
(C) Shows that two theories thought to be in conflict are actually complementary.
(D) Shows that advocates of a theory have not always stated their view in the same manner.
(E) Shows that an implication of a theory is contradicted by the facts.
結構分析：
歡迎來到動物星球頻道
Biologists have long maintained that two groups of pinnipeds, sea lions and walruses, are descended from a terrestrial bear like animal, whereas the remaining group, seals, shares an ancestor with weasels.
首先給出一個理論出來，瞬間有三種動物，一組是ＳＬ跟ＷＡ很像熊，一組是ＳＥ很像ＷＥＡ，分成兩組討論，告訴我們方向，這表示作者八成要借刀殺人，因為開頭用別人講的話幾乎都是準備打槍他的，不多贅述往下。
But the recent discovery of detailed similarities in the skeletal structure of the flippers in all three groups undermines the attempt to explain away superficial resemblance as due to convergent evolution-the independent development of similarities between unrelated groups in response to similar environmental pressures.
開頭出現轉折，所以上面那理論是錯的，因此打槍後講出作者自己的心聲，利用 skeletal structure解釋那三種動物，很明顯不是這麼一回事，只要記住undermines表負向字即可，後面像是the attempt to explain away superficial resemblance as due to convergent evolution-the independent development of similarities between unrelated groups in response to similar environmental pressures.都先不要管他，內容主幹知道即可，其他都是細節只會自己嚇自己。
Flippers may indeed be a necessary response to aquatic life, turtles, whales, and dugongs also have them.
百分之百的舉例，為什麼，因為Flippers，他在上一句有出現過，the flippers in all three groups，而且他也不是主幹，他是作為skeletal structure的修飾詞，理所當然跳過不看。
But the common detailed design found among the pinnipeds probably indicates a common ancestor.
每當轉折都要注意一下 the common detailed design這是代名詞再說上面那個適合水中生活的魚鰭Flippers，所以這轉折其實把原本認為鰭是用來適應水中生活的，轉而說不對，他其實是表示來自同一祖先的證據，這裡隱約可以發現他們的對立性，就是外在環境VS.內部基因，然後轉折後取轉折後內容為主，因此作者認為這鰭是因為基因的關係，不是為了生存水中用的。整體來說這句話是跟上一句當作舉例的Flippers may indeed...兩者擺在一起的，所以不用看也無所謂，況且開頭就給了代名詞了，都是作為上面的補充。
Moreover, walruses and seals drive themselves through the water with thrusts of their hind flippers, but sea lions use their front flippers.
在另外補充一個例子，跳過，邏輯維持不變。
If anatomical similarity in the flippers resulted from similar environmental pressures, as posited by the convergent-evolution theory, one would expect walruses and seals, but not seals and sea lions, to have similar flippers.
開頭這表示條件子句，跳過。
總結一下就是，本來科學家說SL/ WA/ SE這三種分法已經分好了，但是最近理論用鰭的結構去看，發現不對，照理說文章到這裡整個主幹已經結束，只有兩句話，可是他只有打槍說不是之前的理論，但是沒說到新的理論因該如何，然後我們直接跳到But the common detailed design.....這鰭告訴我們跟基因遺傳很有關，這裡就把剛剛的疑惑給補足了，不過其實可以不用知道是遺傳關係，這都是細節了，有考再看
1.The author implies that which of the following was part of the long-standing view concerning pinnipeds?
(A) Pinnipeds are all descended from a terrestrial bear like animal.
(B) Pinnipeds share a common ancestor with turtles, whales, and dugongs.
(C) Similarities among pinnipeds are due to their all having had to adapt to aquatic life.
(D) There are detailed similarities in the skeletal structure of the flippers in all pinnipeds.
(E) Convergent evolution cannot account for the similarities among pinnipeds.
解題：
考推理題，就是要去做對象對比的動作，因此題目問到的事老觀點，所以必需存新觀點出發找到文章內容之後在對內容取『反』，為什麼取反，新舊觀點不同啊中間才有個but。所以這考試重點就是剛剛故意忽略不看的那這很抽很長的句子。
But the recent discovery of detailed similarities in the skeletal structure of the flippers in all three groups undermines the attempt to explain away superficial resemblance as due to convergent evolution-the independent development of similarities between unrelated groups in response to similar environmental pressures.
這麼長就是要拆。首先到undermines the attempt這應該沒問題，the attempt就是代名詞去代替後方這一大串到句尾，explain away反正就取『反』就對了，去削弱一個企圖，然後這個企圖事抵抗superficial resemblance，然後這個superficial resemblance是什麼，用as介系詞補充這個表面相似性就是從convergent evolution來的，在更後方的破折號影出一組同位語，也就是說convergent evolution＝the independent development of similarities，然後這獨立發展得相似性是跟environmental有關，所以整合起來就是新觀點要去抵抗相似性是跟environmental有關的訊息，所以取反之後就是就觀點的內容了，（Ｃ）to adapt to 『aquatic』 life.跟environmental對應到，選（Ｃ）
補充：
這句長難句想了解的話請參考：
2.The author implies which of the following about the fact that turtles, whales, and dugongs all have flippers?
(A) It can be explained by the hypothesis that turtles, whales, and dugongs are very closely related.
(B) It can be explained by the idea of convergent evolution.
(C) It suggests that turtles, whales, and dugongs evolved in separate parts of the world.
(D) It undermines the view that turtles, whales, and dugongs are all descended from terrestrial ancestors.
(E) It is the primary difference between turtles, whales, and dugongs, on the one hand, and pinnipeds, on the other.
解題：
又來推理題，題目上說的東西，對應到原文
Flippers may indeed be a necessary response to aquatic life, turtles, whales, and dugongs also have them.
畢竟是推理題，答案當然不是找到之後往選項帶入就是答案了，我們換個方式用抓主旨的方式來解題，因為這句話的功能是舉例，所以當前方沒有轉折字出現時，他必然是支持上一句表示概念的內容，所以這句話就是去支持a necessary response to aquatic life，然後往前找何謂aquatic就是答案了，前方給你個similar environmental pressures可是他為同位語結構修飾前方convergent evolution，選（Ｂ）
補充：
其實這一題要兩兩分組抓在一起看才比較好懂：
Biologists have long maintained that two groups of pinnipeds, sea lions and walruses, are descended from a terrestrial bear like animal, whereas the remaining group, seals, shares an ancestor with weasels. But the recent discovery of detailed similarities in the skeletal structure of the flippers in all three groups undermines the attempt to explain away superficial resemblance as due to convergent evolution-the independent development of similarities between unrelated groups in response to similar environmental pressures.
這兩句是做『概念』對比。
Flippers may indeed be a necessary response to aquatic life, turtles, whales, and dugongs also have them. But the common detailed design found among the pinnipeds probably indicates a common ancestor.
這兩句做『舉例』對比
3.In presenting the argument in the passage, the author does which of the following?
(A) Contends that key terms in an opposing view have been improperly used.
(B) Contends that opponents have purposely obscured important evidence.
(C) Shows that two theories thought to be in conflict are actually complementary.
(D) Shows that advocates of a theory have not always stated their view in the same manner.
(E) Shows that an implication of a theory is contradicted by the facts.
解題：
結構圖總算派上用場了，結構圖大概在說『新』的理論利用觀察骨骼結構的方式，去反駁『舊』觀點，觀察骨骼結構這是具體證據，所以整個文章是以具體的東西去打趴既有觀點抽象概念，所以選項一定要有表達具體的概念名詞，（Ｂ）evidence，（Ｅ）the facts保留，然後邏輯取反用上去發現具體的東西是去削弱理論的，（Ｂ）描述相反，選（Ｅ）
4. select the sentence in the passage in which the author shows that the implication of the common view is contradicted by a new finding.
這題等於是上面一提的延伸，若由觀點view出發，必然是觀點對觀點，本文有觀點表述的只有前兩句，其他都是舉例，如同結構圖上一般，所以common view的對立面就是第二句了，
But the recent discovery of detailed similarities in the skeletal structure of the flippers in all three groups undermines the attempt to explain away superficial resemblance as due to convergent evolution-the independent development of similarities between unrelated groups in response to similar environmental pressures.
以上筆記供大夥參考若有錯誤再煩請指教
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